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For more information about skin conditions and treatment, contact:


Elizabeth H. Hamilton, MD, PhD
Amy Stein, MD
Julie Dodge, PA-C
4321 Medical Park Dr., #102
Durham, NC 27704
Telephone: (919) 220-7546 (SKIN)

Testing Helps Identify a Variety of Skin Issues

Patients seeking relief for a skin condition can be assured that the first thing a dermatologist will do is ask them to show them their symptoms—the first step to relief. At Regional Dermatology of Durham, Dr. Elizabeth Hamilton, Dr. Amy Stein, and Certified Physician Assistant Julie Dodge are expert skin detectives seeking clues to a diagnosis based on their collective experience.

The practitioners of Regional Dermatology of Durham, from left: Julie Dodge, PA-C, Amy Stein, MD, Elizabeth Hamilton, MD, PhD.

“Diagnosis in dermatology is largely based on appearance and on patterns,” explains Dr. Hamilton. “Sometimes the process is very simple. You look at a rash and recognize it immediately. But at other times, diagnosis is more complicated. Questions have to be asked, a health history taken, and then, perhaps, further testing is needed to come to a conclusive diagnosis.”

Health&Healing: After the initial visual examination what is the next diagnostic step?

JULIE DODGE: The next step, after obtaining a good health history, is to assess their symptoms—and, importantly—how they are treating their symptoms? What medications are they taking? What over-the-counter treatments are they using? What skin care products are they using?

Next, doing a thorough review of body systems is helpful to see if there is any other system involved. It’s not unusual to first suspect that the presenting problem is one condition only to discover, upon thorough examination, that it is, in fact, something else entirely. Which is one reason we always want the patient to bring in all medications that they’re taking.
For example, I recently had a patient who I immediately knew had a drug rash. But she said she was not taking any new meds, and was therefore sure it couldn’t be a drug rash. However, it actually is possible to develop a rash to a drug you’ve used for a long time, so we gave her medication for the rash, but it persisted.

At her next visit, I learned that she had forgotten to tell us about another medicine she was using, for another condition. This went on for several visits and then we discovered that she had also started using a new cleanser and moisturizer. At this point, I wasn’t sure if it was the meds she was taking or if she was allergic to wood alcohol or lanolin in those products. If she had initially given me all this information, it would have saved her pain, office visits, and I would have had a quicker, more useful diagnosis.

H&H: Aren’t there tests that could prevent a lot of trial-and-error evaluation?

DR. STEIN: There certainly are fancy tests, procedures, and studies that people can have, and sometimes need. But so often today, people have extremely high deductibles or co-insurance. Frequently, these expensive tests are unnecessary if you take a detailed history and physical. And, maybe most important, they would be unnecessary if patients would bring all medicines and other products they are using to their exams. Otherwise time is wasted and they’re miserable. And when I say “all,” I mean all medications—prescription and OTC; all supplements; and especially all products they are using on their skin—lotions, moisturizers, cleansers—everything.

The truth is that many body products have potential allergens or irritants that are marketed to help people but, in fact, don’t. And individual patients respond differently to these ingredients.

So we play detective, and we need people’s help because we’re not with them 24/7 to see what they’re doing and what meds they may be taking. Knowing all the basics is really fundamental to diagnosing symptoms. We can do a biopsy and find out that a patient is experiencing allergic contact dermatitis or a drug reaction. But that’s another whole set of tests that are inconvenient and expensive. Sometimes a simple history eliminates the need.

One of my patients had a rash on her face and chest whenever she went out in the sun. As dermatologists, we have to make sure we’re not dealing with a photo sensitivity disorder, such as lupus. Obviously, we don’t want to miss something going on internally. When I asked this patient about her sunscreen, she replied that she had been using it forever and it’s absolutely not the cause of her rash. And she wasn’t using any other new skin products. We talked about changing her sunscreen to something with no fragrance or preservatives.

In another visit, she came still dealing with the same symptoms—and still convinced that her sunscreen was not at the root of her problems. I then biopsied her to make sure this was not a lupus issue or another photo sensitivity problem. The test result revealed the issue: allergic contact dermatitis: something was coming in contact with her skin that we still hadn’t identified, probably, in fact, related to her sunscreen. If she had simply made the change after the first visit we could have solved this easily and quickly.

These kinds of occurrences happen frequently and that’s the beauty of dermatology—having the ability to biopsy rashes if we’re unsure of their cause. A skin biopsy is not a super invasive procedure.

H&H: More complicated cases require more extensive testing.

DR. HAMILTON: Some of the tests we do can lead to more testing. Skin eruptions usually don’t require follow-up tests, but further testing is required to determine lupus and autoimmune disorders. If a rash is biopsied, it can have changes consistent to lupus, dermatomyositis, or any kind of connective tissue disorder. Sometimes there are subtle changes you can see in the skin exam that will help us decide which path to follow, but ultimately that would be a classic example of a biopsy that requires further testing. After having a biopsy, it’s all blood work. A lupus test allows us to see the pattern to define what type of autoimmune disorder it is. Tests are also helpful to ascertain the level of severity of a disease. We may also do a urinalysis to check for protein to see if there is systemic involvement.

There are some biopsies that lead to secondary follow-up biopsies. An example would be some blistering conditions that we see. These patients have antibodies to proteins in their skin that are causing their blisters. We might do a routine H&E (Hematoxylin and Eosin) biopsy, which stains cells different colors so you can visualize them clearly. And then there’s a special test called immunofluorescence where they actually take the skin and look for specific antibodies that are binding to the skin and causing blisters—most common in a condition called pemphigoid, which causes big blisters. Sometimes small blisters can look like fluid-filled bug bites—an early form of bullous pemphigoid.

I once had a middle-aged patient who was very ill. He had seen a rheumatologist and other specialists. Clinically, he had obvious significant disease, but his blood work was normal. I was seeing him for skin cancer. At the end of our visit he mentioned that he had something else going on—obvious but very subtle signs of an autoimmune disorder. His one fingernail showed signs of permanent capillary loops—a bright nail cuticle with other changes of the skin that are significant. We biopsied it and it showed some poorly defined dermatomyositis connective tissue disease. The only thing that substantiated that was the skin biopsy. All the other blood tests had been normal despite it being a pretty severe blood disease. He just had one little finger that looked funny so we biopsied it. The rheumatologist was very appreciative.